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On equatorially trapped boundary inertial waves

Published online by Cambridge University Press:  26 April 2006

K. Zhang
K. Zhang
Affiliation:
Department of Mathematics, University of Exeter, Exeter, EX4 4QJ, UK
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Abstract

Solutions of the Poincaré equation describing equatorially trapped three-dimensional boundary travelling waves in rotating spherical systems are discussed. It is shown that the combined effects of Coriolis forces and spherical curvature enable the equatorial region to form an equatorial waveguide tube with characteristic latitudinal radius (2/m)1/2 and radial radius (1/m), where m is azimuthal wavenumber. Inertial waves with sufficiently simple structure along the axis of rotation and sufficiently small azimuthal wavelength must be trapped in the equatorial waveguide tube. The structure and frequency of the inertial waves are thus hardly affected by the presence of an inner sphere or by the condition of higher latitudes. Further calculations on rotating spherical fluid shells of finite internal viscosity and stressfree boundaries are also discussed.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 248 , March 1993 , pp. 203 - 217
Copyright
© 1993 Cambridge University Press

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